Flexible joint



y 1931. G. FLINTERMANN 1,803,606

FLEXIBLE JOINT Filed Aug. 9, 1927 INVENTOR ATTORNEYS Patented May 5, 1931 UNITED STATES GERHARD FLINTERMANN, OF WEST ORANGE, NEW JERSEY FLEXIBLE JOINT Application filed August 9, 1927. Serial No. 211,839.

This invention relates to flexible joints of the kind disclosed in my copending application, Serial No. 187,156, filed April 28, 1927.

One object of the invention is to provide a .5 flexible joint whichin general operates upon the same principle as that disclosed in the above mentioned application, but which embodies certain improvements. The flexible joint to be herein described is so constructed so that the manufacturing cost is reduced to a minimum. Furthermore, the construction is such that the parts may be readily assembled and readily disassembled forlreplacement of parts should this be necessary.

The improved flexible joint is illustrated in the accompanying drawings in which:

Fig. 1 is a side elevation of the improved joint used as a support for a seat;

Fig. 2 is a front elevation of the joint shown in Fig. 1;

Fig. 3 is a longitudinal section through the joint;

Fig. 4 is a, vertical transverse section taken on the line H of Fig. 3;

- Fig. 5 is a horizontal section taken on the line 55 of Fig. 3;

Figs. 6 and 7 are partial transverse sections corresponding with the section shown in Fig. 4 illustrating modifications of the invention.

The particular flexible joint illustrated in the drawings was designed especially for use as a flexible support for seats, and this particular application of the invention will be described in detail. V

.In the drawings a seat is represented at 1.

This may be an automobile seat, the seat of a railway car or any other seat which it is desired to support in a yielding or flexible manner.

The I joint comprises an outer member 2, preferably supported on the floor or other rigid surface, and an inner member 3 secured to the bottom of the seat by a plate or arm 4. There is a space between the outer member 45 2 and the inner member 3 and this space is occupied by a body of resilient material 5, such as rubber. The space between the inner andouter members is in the form of an elongated annulus andthe resilient materlal occupying 9 this space is correspondingly shaped. Inasmuch as the inner member 3 is capable of a limited vertical movement with respect to the outer member 2, and is also capable of a longitudinal tilting movement with respect to the outer member 2, and inasmuch as the seat is connected to the inner member, it is obvious that the seat is likewise capable of a vertical movement and a backward tilting movement. These movements are yieldingly resisted by the bodyof resilient material 5. When the seat tilts backwardly the maximum compression of the rubber will take place at the points marked a and b and therefore the elongated annulus of resilient material is so shaped that it will have agreater thickness in the vicinity of these places.

The general arrangement of parts thus far described is substantially the same as disclosed in the copending application above referred to. The present improvements deal more with the detail construction of the inner and outer members and the manner in which they are assembled.

The outer member 2comprises an upper plate 2and a lower plate 2". These two plates are fastened together at their ends as shown at 6. The plates 2' and 2 form a housing for the elongated annulus of resilient material 5. Each plate has a corrugation 7 which forms a groove on the'inner surface of the plate. The resilient material has a correspondingly shaped rib or projection 8 which engages in the grooves in the plates 2 and 2". In this way the resilient material is held against lateral movement and too extensive lateral relative displacement of the members of the joint is opposed. In order that the rib 8 will not occupy too much of the effective width of the rubber at those places where the rubber is thinnest, for instance at the points marked 0 and d, the rib 8 on the rubber preferably varies in height so that the rib is of less height where the rubber is of less thickness. That is, when the upper and lower portions of the rubber annulus are 9 tapered as best shown 111 Fig. 3, then the corresponding portions of the encircling rib 8 will be tapered accordingly. The corrugation 7 which receives the rib 8 likewise tapers in depth.

The outer member is shown supported on the floor by means of standards 9 and 10. A convenient way to attach the outer member to the standards 9 and 10 is to insert a bentover portion 11 of each standard between the corresponding ends of the plates 2 and 2 when th y are fastened together.

The inner member, in the form of the jointshown in Figs. 1 to 5 inclusive, preferably comprises a plate 3 which is rigidly secured to the arm 4. These parts may be made in one piece as shown in the drawing. Located over the plate 3, but spaced from it, is a second plate 3. These plates may be held separate by an interposed spacer made up oi? an upper section 12, an intermediate section 123 and a lower section 14. The upper and lower sections 12 and 14 may, if desired, be made of rubber or other resilient material having grea or or degree of flexibility than the surrounding body of resilient material 5. lf desired, these sections may be made of hard material. The intermediate section 13 may be a shim or strip of any suitable material which is inserted between the two sections 12 and 14 to force them apart and to hold the plates 3 and 3 against the inner surface of the annulus 5. The plates 3 and 3 together with the interposed sections 12, 13 and 14 therefore constitute a core of regulated or variable thickness because the thickness of this core may be regulated by using shims 13 of various thickness or by using different numbers of them. The adjustment of the total thickness of this core member may be obtained in any other suitable way. This adjustment of the inner member compensates, when the device is assembled, for variations in the thickness or density of the outer annulus of resilient material. In molding rubber it is dil'licult to get a uniform product and it often varies slightly in thickness and density. lVhen the core member is adjustable it may be made to properly lit the central openingin the annulus 5 when the outer plates 2 and 2 are clamped together.

The inner member including the sections 12 and 14 is preferably tapered from one end to the other with the wide end located at the forward end of the joint and the narrow end located at the rear end of the joint as shown in the drawing. This gives a greater total thickness of rubber over the forward end of the plate 3 and reduces the thickness of the rubber over the rear end of this plate where it is not needed, and permits a corresponding increase in the thickness of the rubber under the rear end of this plate where such an increase in thickness is desirable.

The inner plates 3 and 8 may be provided with corrugations 15 and 16 respectively, similar to and for the same purpose as the corrugations 7 on the outer plates, and the inner sections 12 and 14 of the rubber may have corresponding ribs which engage in the hollows of the corrugations 15 and 16. The corrugations 15 and 16 and also the ribs on the rubber sections 12 and 14 may gradually vary or taper in depth in the same manner as described in connection with the corrugations 7 and the corresponding ribs engaging in them, and for the same purpose.

It will now be seen that the plate 16 supports the seat on the strip of rubber or other resilient material located below it. This plate tilts backwardly with the seat and as it tilts itcompresses the resilient material 5 in the vicinity of the point marked Z). As the entire inner core including the plate 3 and interposed sections 12, 13 and 14 move with the lower plate 3 these members all act as one unitary member to also compress the resilient material 5 in the vicinity of the point marked a. However, when the sections 12 and 14 between the plates 3 and 3 are made of resilient material such as rubber there will also be a yielding action between these plates which may be desirable in some instances. By properly correlating the respective resiliences of the inner and outer bodies of resilient material, that is, the inner body 12, 14 on the one hand and the outer body 5 on the other hand, the desired action of the joint may be obtained. Another advantage of making the inner sections 12, 14 of resilient material is that if it is desired to change the resiliency of the joint this may be elfected without changing the larger and more expensive body of resilient material 5, but by changing the inner and less expensive body of resilient material 12, 14.

Instead of fastening the arm or plate 4 directly to the bottom of the seat 1 it may be fastened to one arm of a hinge 17 which in turn is secured to the bottom of the seat. In this way the seat may be tilted forwardly to gain access to the compartment under the seat. This may be a desirable feature in automobiles, for instance.

In order to limit the backward tilting movement of the seat a rubber stop 18 is provided which is preferably mounted on an ad justable support 19. By adjusting the position of the stop 18 it may be made to act at the desired time during the backward tilting of the seat and its effect in opposing and limiting the tiltingof the seat may thus be varied. By rendering the stop 18 more'or less effective, it is obvious that the action of the flexible joint may be modified to make it more resistent or more resilient as required.

In the modification shown in Fig. 6 the inner member comprising the plates 3 and 3 and interposed sections 12, 13 and 14 in the preceding figures is replaced by a solid mem- -ber 20, which if desired may be a casting, forging or pressed member.

In Fig. 7 the corrugation 7 on each of the outer plates is shown out of alignment with the corrugation on the corresponding inner plate. is represented in this figure as being in one piece. These may be desirable modifications in some instances.

Practically all of the metallic parts of the flexible joint may be made of pressed or stamped sheet metal, such as steel, and yet the necessary strength is obtained. The ribs 7 on the plate 2 and 2" and the ribs 15 and 16 on the plate 3" and 3 reinforce and strengthen these plates and at the same time confine or hold the resilient material against lateral movement and prevent too extensive lateral relative displacement between the members of the joint. Side plates are therefore not necessary for confining the resilient material thus simplifying the construction and lessening the cost of manufacture to a corresponding extent. Another advantage of the elimination of the side plates is that the rubber may flow more readily in a lateral direction while at the same time being held against laterial displacement by the ridges and groves in the plates and rubber. The edges of the plates may be turned slightly if desired as shown in Figs. 4:, 6 and 7, mainly for the purpose of strengthening the plates at their edges.

The elongated annulus 5 of rubber or other resilient material may be made in two parts as shown in Fig. 3 or in more parts if desired.

When the joint is assembled the rubber annulus is placed around the inner member and then clamped between the outer plates 2 and 2. If, when the plates 2 and 2 are clamped together, it is found that the inner member is too small it may be made wider as described above. If it is found that the inner member is too wide to allow the plates 2 and 2 to be clamped together properly it may be made narrower.

The plates 2 and 2 being alike, may be made by the same dies, thus simplifying and lessening the cost of manufacture.

While the improved flexible joint has been shown and described as a support for seats it may be used for numerous other purposes, for instance, as a cushion support for various devices such as the motors and compressors of refrigration machines, or it may be used as a flexible joint between any two members regardless of whether or not it serves as a support.

The drawings show only one end of the seat and only one flexible joint. The joint may be duplicated at the other end of the seat and supported on the floor in the same manner as described above, or in the case of a seat for railway cars, for instance, the joint at one end of the seat may be supported on a wall.

By properly positioning the flexible joint, or joints, with respect to the forward and rear edges of the seat the proper inclination The body between the plates 3 and 3 l of the seat may be obtained as it tilts. The hinge l7 affords convenient means for attaching the bottom ofthe seat tothe joint at theproper place, becausethe upper leaf of the hinge may be attached to the seat while the seat is tilted forwardly. If it is desired to change the position of the seat with respect to the joint, or joints, it is only necessary to tilt the. seat forwardly and then change the point of attaclimentofthe upper leaf of the hinge. v l

p The inner member of the joint practically floats in the outer member for all directions of movement. That is, the inner member is not only capable of a limited movement vertical and diagonally as described above, but also sidewise. 1 it I claim:

1. A flexible joint comprising an annulus of resilient material, a sheet metal member surrounding said annulus, and an inner member engaging in the opening in said annulus ofresilient material, said sheet metal member being longitudinally divided into two sections so that each of the sections engages with the resilient material throughout a portion only of the outer circumference of the annulus, and means for fastening said sections together.

2. A flexible joint comprising an elongated annulus of resilient material, a member surrounding the same, and an inner member engaging in the opening in said annulus of resilient material said inner member comprising a pair of plates and an interposed spacer, one of said plates being adapted for attachment to an object in connection with which the flexible joint is employed.

3. A flexible joint in accordance with claim 2 in which said spacer comprises a body of resilient material.

4:. A flexible joint in accordance with claim 2 in which said spacer comprises two bodies of resilient material and an interposed shim.

5. A flexible joint comprising an annulus of resilient material, a metal member surrounding said annulus, and an inner member engaging in the opening in said annulus of resilient material, said metal member being longitudinally divided into two sections so that each of the sections engages with the resilient material throughout a portion onlyv of the outer circumference of the annulus and means for fastening said sections together.

6. A flexible joint comprising an elongated annulus of resilient material, a member surrounding the same, and an inner member engaging in the opening in said annulus of resilent material, said inner member being composite and made up of several parts including at least two plates and an interposed spacer, each of said plates engaging with the resilient material throughout a portion only of the inner circumference of the elongated annulus, one of the parts of said inner member being adapted for attachment to an object in connection with which the flexible joint is employed.

7. A flexible joint comprising an elongated annulus of resilient material, a member surrounding the same and adapted to be connected to one of the objects between which the joint is to be interposed, an inner member located in the opening in said elongated annulus, said inner member being composite and made of at least three parts, one of said .parts engaging with the resilient materia-l throughout a portion only of the inner circumference of the elongated annulus, the second of said parts engaging with the resilient material substantially throughout the re maining portion of its inner circumference, and the third part being interposed between the first and second parts, one of said parts of the inner member being adapted for at tachment to the otherof the two objects between which the joint is to be interposed.

In testimony whereof I aflix my signature.

GERHARD FLINTERMANN. 

